The present invention relates to a process for producing fluorine atom-containing sulfonyl fluoride compounds useful as e.g. materials for ion-exchange resins, and novel chemical substances useful as intermediates in the process.
Fluorine atom-containing sulfonyl fluoride compounds having a fluoroformyl group (such as the following compound (i)) are useful as materials for ion-exchange resins. Heretofore, compounds having a fluoroformyl group have been synthesized by a process which comprises reacting perfluoroalkylene oxides to a cyclic compound obtainable by the reaction of tetrafluoroethylene with sulfur trioxide (SO3). For example, the following compound (i) can be obtained by reacting hexafluoropropylene oxide (HFPO) to the above-mentioned cyclic compound, as shown by the following formula. 
However, the conventional synthetic process was a disadvantageous process for practical industrial application, since a due care is required for handling SO3. Further, reduction of the price can hardly be accomplished because the difficulty in synthesis is high. In addition, the obtainable compound (i) is limited to a compound having a side chain (xe2x80x94CF3), whereby there has been a problem from the viewpoint of the membrane characteristics of the ion-exchange membrane prepared from a derivative of the compound (i).
The present invention has been made for the purpose of solving the problems of the prior art and provides a process which solves the difficulty in production and whereby fluorosulfonyl fluoride compounds having various molecular structures can be produced efficiently and at low costs.
The present inventors have invented a process which comprises reacting a sulfonyl halide compound having a certain specific structure with fluorine in a liquid phase, followed by decomposition of the product, and have found it possible to thereby carry out a process for producing the desired fluorine atom-containing sulfonyl fluoride compounds.
Namely, the present invention provides a process for producing fluorine atom-containing sulfonyl fluoride compounds, which comprises reacting a compound of the following formula (1) with a compound of the following formula (2) to form a compound of the formula (3), then, reacting the compound of the formula (3) with fluorine in a liquid phase to form a compound of the following formula (4), and further, decomposing the compound of the formula (4) to obtain a compound of the following formula (5):
XSO2RA-E1xe2x80x83xe2x80x83(1)
RB-E2xe2x80x83xe2x80x83(2)
XSO2RA-E-RBxe2x80x83xe2x80x83(3)
FSO2RAF-EF-RBFxe2x80x83xe2x80x83(4)
FSO2RAF-EF1xe2x80x83xe2x80x83(5)
wherein RA is a bivalent organic group, E1 is a monovalent reactive group, RB is a monovalent organic group, E2 is a monovalent reactive group which is reactive with E1, E is a bivalent connecting group formed by the reaction of E1 with E2, RAF is the same group as RA, or a bivalent organic group formed by the fluorination of RA, RBF is the same group as RB, or a monovalent organic group formed by the fluorination of RB, EF is the same group as E, or a bivalent connecting group formed by the fluorination of E, EF1 is a monovalent group formed by the decomposition of EF, and X is a halogen atom, provided that at least one of RA, RB and E is a group which can be fluorinated, and at least one of RAF, RBF and EF is a group formed by the fluorination of RA, RB and E, respectively.
Further, the present invention provides the above process, wherein the compound of the formula (4) is decomposed to obtain not only the compound of the formula (5), but also a compound of the following formula (6):
RBF-EF2xe2x80x83xe2x80x83(6)
wherein EF2 is a monovalent group formed by the decomposition of EF, which may be the same as or different from EF1, and RBF is as defined above.
Further, the present invention provides the above process, wherein the compound of the formula (1) is a compound of the following formula (1a), the compound of the formula (2) is a compound of the following formula (2a), the compound of the formula (3) is a compound of the following formula (3a), the compound of the formula (4) is a compound of the following formula (4a), and the compound of the formula (5a) is a compound of the following formula (5a):
XSO2RAxe2x80x94CH2OHxe2x80x83xe2x80x83(1a)
RBxe2x80x94COYxe2x80x83xe2x80x83(2a)
XSO2RAxe2x80x94CH2OCOxe2x80x94RBxe2x80x83xe2x80x83(3a)
FSO2RAFxe2x80x94CF2OCOxe2x80x94RBFxe2x80x83xe2x80x83(4a)
FSO2RAFxe2x80x94COFxe2x80x83xe2x80x83(5a)
wherein Y is a halogen atom which is the same as or different from X, and RA, RB, RAF and RBF are as defined above.
Further, the present invention provides the above process, wherein the compound of the formula (4a) is decomposed to obtain not only the compound of the formula (5a), but also a compound of the following formula (6a):
RBFxe2x80x94COFxe2x80x83xe2x80x83(6a)
wherein RBF is as defined above.
Further, the present invention provides the above process, wherein the compound of the formula (2a) has the same structure as the compound of the formula (6a), and at least a part of the compound of the formula (6a) obtained from the reaction product obtained by the decomposition of the compound of the formula (4a), is used as at least a part of the compound of the formula (2a) to react with the compound of the formula (1a), to continuously obtain the compound of the formula (5a).
Further, the present invention provides a compound of the following formula (I) or a compound of the following formula (II):
FSO2CH2CH2OCH2CH2OCOCF(CF3)OCF2CF2CF3xe2x80x83xe2x80x83(I)
FSO2CF2CF2OCF2CF2OCOCF(CF3)OCF2CF2CF3xe2x80x83xe2x80x83(II)